Wastewater Numbers And Percents

Front 1

Primary Clarifiers remove ____ to ____% Inf BOD

Back 1

20% to 40%

Front 2

Primary Clarifiers remove ___% (TSS) Inf solids.

Back 2

50%-70%

Front 3

Nitrification is stopped at what temperature?

Back 3

5-10 degrees Celsius

Front 4

Strong BOD domestic wastewater concentration is_____mg/l.

Back 4

350-500 mg/l

Front 5

Normal domestic BOD concentration is ___mg/l.

Back 5

200-250 mg/l

Front 6

Normal running anaerobic digesters reduce___ to__% solids.

Back 6

50%-60%

Front 7

Methane Fermenters need a PH of ____ to properly reproduce.

Back 7

6.6 - 7.6

Front 8

Primary Clarifiers remove ____% settlable solids.

Back 8

95%-99%

Front 9

Nitrification and Denitrification have a PH of ___ to__to run properly.

Back 9

7.8 - 8.2

Front 10

Normal anaerobic digesters have a ___ to___% methane content by volume.

Back 10

65% - 70%

Front 11

A typical MLSS concentration in the Activated Sludge Process is ____mg/l.

Back 11

1000 - 4000 mg/l

Front 12

It's safe to work a 40 hour work week with a chlorine gas exposure of ___ppm.

Back 12

0.5 ppm

Front 13

Chlorine gas is_____times heavier than air.

Back 13

2.5

Front 14

Typical BOD removal in a Facultative Pond is____ to ___%

Back 14

70% - 80%

Front 15

Typical Detention Time in a Primary Clarifier is _____hrs.

Back 15

1.5 - 2 hrs

Front 16

Normal anaerobic digestion has a carbon dioxide content of ___% by volume.

Back 16

30% - 35%

Front 17

Entering a confined space is oxygen deficient when it is ___%.

Back 17

<19.5%

Front 18

Typical bacterial removal in a Primary Clarifier is ____ to___%.

Back 18

25% - 75%

Front 19

Domestic raw wastewater has a PH of___ to ___.

Back 19

6.8 - 8.0

Front 20

Typical suspended solids removal in a Primary Clarifier is ____ to ____%.

Back 20

40% - 60%

Front 21

Typical MLSS concentration is usually ______mg/l.

Back 21

1000 mg/l to 4500 mg/l

Front 22

Typical BOD concentration in a secondary clarifier is __to__mg/l.

Back 22

5 - 30 mg/l

Front 23

Good, thick primary sludge is __ to__% dry solids.

Back 23

4% - 8%

Front 24

Grit will properly settle at what speed?

Back 24

1 ft/sec

Front 25

Sedimentation Basins have a settleable rate of ____hrs.

Back 25

2- 3 hrs

Front 26

WAS rate shouldn't change more than _____% from one day to the next?

Back 26

10% - 15%

Front 27

MLVSS and MLSS ratio in an ASP should be between ______.

Back 27

0.7 and 0.8

Front 28

There are _____U.S. gallons in a cubic ft.

Back 28

7.48

Front 29

7.48 U.S. gallons per cubic foot is equivalent to ______ lbs/gal.

Back 29

8.34

Front 30

Generally, specific gravity of municipal sewage lies between _____.

Back 30

1.2 and 1.4 --- which is slightly greater than 1

Front 31

1 ppm of dissolved oxygen in water equals ___lb of oxygen in ___lbs of water.

Back 31

1lb, 1,000,000 lbs

Front 32

A number used in horsepower math is _____.

Back 32

3960

Front 33

An Acidic PH range is ________.

Back 33

0 to 6.9

Front 34

A Basic PH range is______.

Back 34

7.1 to 14.0

Front 35

Typical dissolved oxygen in an aeration tank is ______mg/l.

Back 35

2 - 4 mg/l.

Front 36

MLVSS should be between _______ % and______% of the MLSS.

Back 36

70% and 80%

Front 37

Maintain a dissolved oxygen concentration of _____mg/l or higher for optimum nitrification.

Back 37

2.0 mg/l

Front 38

PH below _____ or above ____ can inhibit nitrification.

Back 38

6.5, 8.0

Front 39

Maintain a dissolved oxygen concentration below _____mg/l in an anoxic zone to achieve denitrification.

Back 39

0.3 mg/l

Front 40

1 gallon equals _____lbs.

Back 40

8.34

Front 41

1000 mg equals ____ ml.

Back 41

1

Front 42

There are ______ mg in a gram.

Back 42

1000

Front 43

There are ______ml in a liter.

Back 43

1000

Front 44

In process control, don't make incremental changes that exceed _____%.

Back 44

10%

Front 45

Sludge pumps are sized to pump _____% of plant flow.

Back 45

100%

Front 46

Sludge Bulking leaves a clear supernatant, but the SVI is high; usually greater than ______mg/l.

Back 46

150 mg/l

Front 47

When using specific gravity,"dry feed" is what % of the solution?

Back 47

100%

Front 48

A good anaerobic digester reduces volatile solids by_____%.

Back 48

50% - 60%

Front 49

Chlorine gas isn't detected by smell if concentration is:

Back 49

<1PPM

Front 50

Water expands as temperatures _________ above_________.

Back 50

Increase, 4 degrees Celsius

Front 51

What is the wastewater velocity range in ft/ sec for grit removal in a grit chamber?

Back 51

0.7 to 1.4 ft/sec

Front 52

In domestic wastewater, suspended solids range from ____ to ____mg/l.

Back 52

100 to 300

Front 53

In general, the solids content in wastewater is about _____%.

Back 53

0.1

Front 54

What is the typical BOD removal in a Primary Clarifier? (%)

Back 54

20 - 50%

Front 55

For each ft of height of a water column, the pressure increases______psi.

Back 55

0.433

Front 56

Each ____ ft of elevation of a column of water generates 1.0 psi.

Back 56

2.31

Front 57

Horsepower equals _____ ft-lbs/sec.

Back 57

550

Front 58

1 horsepower equals _____ watts or _______ kilowatts.

Back 58

746, .746